Six NIH-funded, health-related projects and three other projects requiring the use of a combined gas chromatograph-mass spectrometer (GCMS) are being carried out in the Department of Microbiology & Public Health at Michigan State University. The only GCMS available for these projects is currently located in the Department of Biochemistry, MSU, and it has limited availability. The instrument requested in this BRS-Shared Instrumentation Grant is a new Hewlett Packard Model 5995C GCMS with complete computer capability. It would be located in R. 158 Giltner Hall, and be used by at least five different research groups in the Department of Microbiology & Public Health. This instrument would be used to separate, identify, and quantitate glycosyl components and to establish their glycosidic linkages in the capsular polysaccharides and lipopolysaccharides of Rhizobium trifolii, in lipopolysaccharides of Yersinia pseudotuberculosis and Y. enterocolitica, and in glycoconjugates on the cell surfaces of trypanosome protozoan parasites and their mammalian host. The instrument would also be used to identify metabolic intermediates in the microbial synthesis of resorcinolic and pyrone-2-one type lipids during cyst differentiation in Azotobacter vinelandii, and in the anaerobic microbial metabolism of various classes of environmentally important compounds, including chlorinated hydrocarbons, polyethylene glycols, and nitrite. This GCMS instrument would enhance the planned research endeavors of the major users since the demand for GCMS at MSU far exceeds the availability of such instruments and GCMS is one of the major analytical instruments required for our funded research. Appropriate technical expertise within the group of each major user is available, and an institutional commitment for continued support of the utilization and maintenance of the instrument has been made with the major user group, the Department of Microbiology & Public Health, the College of Natural Science, and the Michigan Agricultural Experiment Station at MSU.